Originally Posted by
BlueLiger
Would a 17 Pal 3 Fighter Split be better for the build?
In any build decision, the key question is "If I change X, am I gaining more than I'm losing?".
In DDO, one of the biggest build considerations is Enhancements (something that does not exist in D&D). Most Classes have 3 trees to choose from, and each tree has both Tiers (I-V), and the Cores, which are (typically) more powerful.
By suggesting Fighter 3, I'm guessing you're looking at one of the Tier 3 Fighter enhancements - but what about the Paladin Core 18 and 20 enhancements you're losing?
Cores are gated at Level 1, 3, 6, 12, 18 and 20, with (usually) the best at the highest level. So, many (but not all) classes want "pure" to get that Level 20 core (aka the "capstone"), but some Core 20 Enhancements are not so great that they are "must have", and this opens the door to multi-classing. If the Core 18 is a "must have", then you only have 2* other levels to play with; if you can live with just the Core 12, then you can grab a Core 6 from another class, or 2 Core 3's from 2 other classes to balance the loss of the Core 18/20, etc.
(* It can also be important to consider whether the build is designed to go to 30 (so at least half the questing will be done after all 20 levels are in place), or designed to live at 20(+) for a while (for Heroic farming, for instance), or to get to 20 and TR/RR asap. If that last, then, practically speaking, it's just an "18-level" build, since you get to 18, bank 19 & 20, and then take 20 and do your Reincarnation, and those last 2 levels never see a significant amount of play time. All considerations for a build.)
To truly "understand" how to create a strong, well-designed DDO build, you have to have a solid grasp of all the trees that could be used, to pick and choose, mix and match, find the synergies and avoid the wasted effort. For Paladins, start by looking at their 3 trees (cores and tiers) in the Wiki - https://ddowiki.com/page/Enhancements. It's a long process, don't expect it all to make sense overnight, or even this month. GL!